转GhB301基因棉花响应枯萎病菌侵染的转录组分析

乙烯响应因子(ethylene responsive factor, ERF)可以激活或者抑制下游病程相关蛋白基因的表达,在植物抗病信号转导途径中发挥着重要作用。为探究ERF-B3亚组基因GhB301在棉花抗枯萎病中的分子调控机制,本研究利用已获得的转GhB301基因棉花株系,通过孢子悬浮液蘸根的方法对转GhB301基因棉花株系(N)和野生型对照(WT)进行接菌处理,抗病性鉴定结果表明,过表达GhB301的N株系增强了对枯萎病的抗病性,其病情指数为14.77,显著低于WT(病情指数为37.50);枯萎病菌侵染0、6、12、24、48 h后,利用RNA-seq技术对N和WT的根部组织进行测序分析,共得到273 111 170个clean reads,其Q30均大于87.64%,将clean reads与陆地棉参考基因组TM-1比对,获得了14 021个差异表达基因(DEGs)。与WT相比,转基因株系能够在病原菌侵染后更快速地做出响应。GO及KEGG富集分析发现共有135个DEGs参与氧化还原过程,67个DEGs参与防御反应,31个DEGs参与苯丙烷类生物合成,推测这些DEGs可能与转基因棉花的枯萎病抗性增强存在密切关系。本研究结果为阐明GhB301基因响应棉花枯萎病菌侵染规律奠定了基础。

Transcriptome Analysis of GhB301 Transgenic Cotton Response to Fusarium wilt Infection

Ethylene responsive factor (ERF) plays an important role in the signal transduction pathways of plant disease resistance through activating or inhibiting enhancement the expression of downstream disease-related protein genes. In order to explore the molecular regulatory mechanism of ERF-B3 subgroup gene GhB301 in cotton resistance to Fusarium wilt, using the obtained GhB301 transgenic cotton lines were used as material in this study. The spore suspension was dipped into the roots to transfect GhB301 transgenic cotton strains (N) and wild-type controls (WT). Results of disease resistance identification showed that GhB301 overexpressing of the transgenic cotton lines enhanced their disease resistance to Fusarium wilt with a disease index of 14.77%,which was significantly lower than that of the WT (the disease index was 37.50%). RNA-seq technology was used to sequence and analyze root tissues of fuse-infected N and WT at 0, 6, 12, 24 and 48h after infection. Totally 273 111170 clean reads were obtained,and their Q30 were all greater than 87.64%. The clean reads were compared to the reference genome tm-1 of upland cotton, and 14021 differentially expressed genes (DEGs) were obtained. Compared with the WT, the transgenic strains could respond more quickly after pathogen infection. GO and KEGG enrichment analysis revealed that a total of 135 DEGs were involved in the REDOX process, 67 DEGs were involved in the defense reaction, and 31 DEGs were involved in phenylpropane biosynsynthesis. We speculated that these DEGs may be closely related to the increased Fusarium wilt resistance in transgenic cotton. The results of this study laid a foundation for elucidating the response of GhB301 gene to cotton Fusarium wilt infection..